1. Field of the Invention
The present invention relates generally to apparatus for conveying bulk materials such as mined, nonpacked coal, or ore or nonpacked cereal grain vertically upward in a continuous fashion and more particularly to vertical bulk conveyors of the type including conveying means in the form of two endless conveyor belts arranged in face-to-face overlapping relation to each other for holding bulk material therebetween and an improved bulk feeder combined with such conveying means, and relates also to bulk delivering apparatus utilizing such vertical bulk conveyors.
2. Description of the Prior Art
For the conveying to a higher level of bulk materials, such as coal piled in a coal yard and ore or grain material placed in the holds of a cargo vessel, a vertical conveyor has recently been proposed which includes two conveyor belts arranged to travel in face-to-face overlapping relation to each other upwardly in a substantially vertical direction while holding bulk material between the overlapping belt faces for continuous vertical transportation of the bulk material.
The vertical conveyor is highly excellent as a machine for conveying bulk materials to higher levels in that it does not necessitate any unduly large ground space for installation and is capable of continuous conveying operation with high efficiency. With the vertical conveyor, however, it has previously been unavoidable that its conveyor belts are subjected in operation to more or less strains on account of the means used to feed bulk material to be conveyed between the two conveyor belts. Specifically, in the bottom, bulk feed region of the vertical conveyor, one of the two conveyor belts is guided to travel in a substantially horizontal path so as to be fed with bulk material thereon and, passing under the bottom turning end of the other conveyor belt, comes into overlapping relation therewith so that the bulk material is held between the opposing surfaces of the two conveyor belts, which proceed thereafter upwardly at the same speed. With this arrangement, however, in the region where the first conveyor belt passes around the bottom turning end portion of the second conveyor belt, which proceeds around the periphery of a bottom guide pulley provided therefor, the two conveyor belts must proceed at the same angular velocity through an angle of approximately 90 degrees around the same guide pulley with their opposite side edges laid over each other the guide pulley. Because of this, the first conveyor belt is unduly stretched during its passage around the guide pulley and substantial reduction in service life of such belt results.